huft_build in archival/libarchive/decompress_gunzip.c in BusyBox before 1.27.2 misuses a pointer, causing segfaults and an application crash during an unzip operation on a specially crafted ZIP file. ..read more

Integer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to cause a denial of service (crash) via a malformed RFC1035-encoded domain name, which triggers an out-of-bounds heap write. ..read more

Heap-based buffer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to have unspecified impact via vectors involving OPTION_6RD parsing. ..read more

The recv_and_process_client_pkt function in networking/ntpd.c in busybox allows remote attackers to cause a denial of service (CPU and bandwidth consumption) via a forged NTP packet, which triggers a communication loop. ..read more

In the add_match function in libbb/lineedit.c in BusyBox through 1.27.2, the tab autocomplete feature of the shell, used to get a list of filenames in a directory, does not sanitize filenames and results in executing any escape sequence in the terminal. This could potentially result in code execution, arbitrary file writes, or other attacks. ..read more

Busybox contains a Missing SSL certificate validation vulnerability in The "busybox wget" applet that can result in arbitrary code execution. This attack appear to be exploitable via Simply download any file over HTTPS using "busybox wget https://compromised-domain.com/important-file". ..read more

BusyBox project BusyBox wget version prior to commit 8e2174e9bd836e53c8b9c6e00d1bc6e2a718686e contains a Buffer Overflow vulnerability in Busybox wget that can result in heap buffer overflow. This attack appear to be exploitable via network connectivity. This vulnerability appears to have been fixed in after commit 8e2174e9bd836e53c8b9c6e00d1bc6e2a718686e. ..read more

An issue was discovered in BusyBox before 1.30.0. An out of bounds read in udhcp components (consumed by the DHCP server, client, and relay) allows a remote attacker to leak sensitive information from the stack by sending a crafted DHCP message. This is related to verification in udhcp_get_option() in networking/udhcp/common.c that 4-byte options are indeed 4 bytes. ..read more

An issue was discovered in BusyBox through 1.30.0. An out of bounds read in udhcp components (consumed by the DHCP client, server, and/or relay) might allow a remote attacker to leak sensitive information from the stack by sending a crafted DHCP message. This is related to assurance of a 4-byte length when decoding DHCP_SUBNET. NOTE: this issue exists because of an incomplete fix for CVE-2018-20679. ..read more

A NULL pointer dereference in Busybox's hush applet leads to denial of service when processing a crafted shell command, due to missing validation after a \x03 delimiter character. This may be used for DoS under very rare conditions of filtered command input. ..read more

A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the getvar_i function ..read more

A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the next_input_file function ..read more

A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the hash_init function ..read more

A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the handle_special function ..read more

A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the evaluate function ..read more

A use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the nvalloc function ..read more

BusyBox through 1.35.0 allows remote attackers to execute arbitrary code if netstat is used to print a DNS PTR record's value to a VT compatible terminal. Alternatively, the attacker could choose to change the terminal's colors. ..read more

The nscd daemon in the GNU C Library (glibc) before version 2.5 does not close incoming client sockets if they cannot be handled by the daemon, allowing local users to carry out a denial of service attack on the daemon. ..read more

Multiple integer overflows in the strfmon implementation in the GNU C Library (aka glibc or libc6) 2.10.1 and earlier allow context-dependent attackers to cause a denial of service (memory consumption or application crash) via a crafted format string, as demonstrated by a crafted first argument to the money_format function in PHP, a related issue to CVE-2008-1391. ..read more

Integer overflow in the __vstrfmon_l function in stdlib/strfmon_l.c in the strfmon implementation in the GNU C Library (aka glibc or libc6) before 2.10.1 allows context-dependent attackers to cause a denial of service (application crash) via a crafted format string, as demonstrated by the %99999999999999999999n string, a related issue to CVE-2008-1391. ..read more

Integer overflow in the __tzfile_read function in glibc before 2.15 allows context-dependent attackers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted timezone (TZ) file, as demonstrated using vsftpd. ..read more

In the GNU C Library (aka glibc or libc6) before 2.28, parse_reg_exp in posix/regcomp.c misparses alternatives, which allows attackers to cause a denial of service (assertion failure and application exit) or trigger an incorrect result by attempting a regular-expression match. ..read more

The encode_name macro in misc/mntent_r.c in the GNU C Library (aka glibc or libc6) 2.11.1 and earlier, as used by ncpmount and mount.cifs, does not properly handle newline characters in mountpoint names, which allows local users to cause a denial of service (mtab corruption), or possibly modify mount options and gain privileges, via a crafted mount request. ..read more

Integer signedness error in the elf_get_dynamic_info function in elf/dynamic-link.h in ld.so in the GNU C Library (aka glibc or libc6) 2.0.1 through 2.11.1, when the --verify option is used, allows user-assisted remote attackers to execute arbitrary code via a crafted ELF program with a negative value for a certain d_tag structure member in the ELF header. ..read more

Certain run-time memory protection mechanisms in the GNU C Library (aka glibc or libc6) print argv[0] and backtrace information, which might allow context-dependent attackers to obtain sensitive information from process memory by executing an incorrect program, as demonstrated by a setuid program that contains a stack-based buffer overflow error, related to the __fortify_fail function in debug/fortify_fail.c, and the __stack_chk_fail (aka stack protection) and __chk_fail (aka FORTIFY_SOURCE) implementations. ..read more

elf/dl-load.c in ld.so in the GNU C Library (aka glibc or libc6) through 2.11.2, and 2.12.x through 2.12.1, does not properly handle a value of $ORIGIN for the LD_AUDIT environment variable, which allows local users to gain privileges via a crafted dynamic shared object (DSO) located in an arbitrary directory. ..read more

ld.so in the GNU C Library (aka glibc or libc6) before 2.11.3, and 2.12.x before 2.12.2, does not properly restrict use of the LD_AUDIT environment variable to reference dynamic shared objects (DSOs) as audit objects, which allows local users to gain privileges by leveraging an unsafe DSO located in a trusted library directory, as demonstrated by libpcprofile.so. ..read more

The glob implementation in the GNU C Library (aka glibc or libc6) allows remote authenticated users to cause a denial of service (CPU and memory consumption) via crafted glob expressions that do not match any pathnames, as demonstrated by glob expressions in STAT commands to an FTP daemon, a different vulnerability than CVE-2010-2632. ..read more

The GNU C Library (aka glibc or libc6) before 2.12.2 and Embedded GLIBC (EGLIBC) allow context-dependent attackers to execute arbitrary code or cause a denial of service (memory consumption) via a long UTF8 string that is used in an fnmatch call, aka a "stack extension attack," a related issue to CVE-2010-2898, CVE-2010-1917, and CVE-2007-4782, as originally reported for use of this library by Google Chrome. ..read more

The addmntent function in the GNU C Library (aka glibc or libc6) 2.13 and earlier does not report an error status for failed attempts to write to the /etc/mtab file, which makes it easier for local users to trigger corruption of this file, as demonstrated by writes from a process with a small RLIMIT_FSIZE value, a different vulnerability than CVE-2010-0296. ..read more

locale/programs/locale.c in locale in the GNU C Library (aka glibc or libc6) before 2.13 does not quote its output, which might allow local users to gain privileges via a crafted localization environment variable, in conjunction with a program that executes a script that uses the eval function. ..read more

ld.so in the GNU C Library (aka glibc or libc6) 2.13 and earlier expands the $ORIGIN dynamic string token when RPATH is composed entirely of this token, which might allow local users to gain privileges by creating a hard link in an arbitrary directory to a (1) setuid or (2) setgid program with this RPATH value, and then executing the program with a crafted value for the LD_PRELOAD environment variable, a different vulnerability than CVE-2010-3847 and CVE-2011-0536. NOTE: it is not expected that any standard operating-system distribution would ship an applicable setuid or setgid program. ..read more

Integer overflow in posix/fnmatch.c in the GNU C Library (aka glibc or libc6) 2.13 and earlier allows context-dependent attackers to cause a denial of service (application crash) via a long UTF8 string that is used in an fnmatch call with a crafted pattern argument, a different vulnerability than CVE-2011-1071. ..read more

Integer signedness error in Glibc before 2.13 and eglibc before 2.13, when using Supplemental Streaming SIMD Extensions 3 (SSSE3) optimization, allows context-dependent attackers to execute arbitrary code via a negative length parameter to (1) memcpy-ssse3-rep.S, (2) memcpy-ssse3.S, or (3) memset-sse2.S in sysdeps/i386/i686/multiarch/, which triggers an out-of-bounds read, as demonstrated using the memcpy function. ..read more

The svc_run function in the RPC implementation in glibc before 2.15 allows remote attackers to cause a denial of service (CPU consumption) via a large number of RPC connections. ..read more

scanf and related functions in glibc before 2.15 allow local users to cause a denial of service (segmentation fault) via a large string of 0s. ..read more

Integer overflow in string/strcoll_l.c in the GNU C Library (aka glibc or libc6) 2.17 and earlier allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via a long string, which triggers a heap-based buffer overflow. ..read more

Stack-based buffer overflow in string/strcoll_l.c in the GNU C Library (aka glibc or libc6) 2.17 and earlier allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via a long string that triggers a malloc failure and use of the alloca function. ..read more

iconvdata/ibm930.c in GNU C Library (aka glibc) before 2.16 allows context-dependent attackers to cause a denial of service (out-of-bounds read) via a multibyte character value of "0xffff" to the iconv function when converting IBM930 encoded data to UTF-8. ..read more

Stack-based buffer overflow in the getaddrinfo function in sysdeps/posix/getaddrinfo.c in GNU C Library (aka glibc or libc6) 2.17 and earlier allows remote attackers to cause a denial of service (crash) via a (1) hostname or (2) IP address that triggers a large number of domain conversion results. ..read more

pt_chown in GNU C Library (aka glibc or libc6) before 2.18 does not properly check permissions for tty files, which allows local users to change the permission on the files and obtain access to arbitrary pseudo-terminals by leveraging a FUSE file system. ..read more

Cyrus SASL 2.1.23, 2.1.26, and earlier does not properly handle when a NULL value is returned upon an error by the crypt function as implemented in glibc 2.17 and later, which allows remote attackers to cause a denial of service (thread crash and consumption) via (1) an invalid salt or, when FIPS-140 is enabled, a (2) DES or (3) MD5 encrypted password, which triggers a NULL pointer dereference. ..read more

sysdeps/posix/readdir_r.c in the GNU C Library (aka glibc or libc6) 2.18 and earlier allows context-dependent attackers to cause a denial of service (out-of-bounds write and crash) or possibly execute arbitrary code via a crafted (1) NTFS or (2) CIFS image. ..read more

Multiple integer overflows in malloc/malloc.c in the GNU C Library (aka glibc or libc6) 2.18 and earlier allow context-dependent attackers to cause a denial of service (heap corruption) via a large value to the (1) pvalloc, (2) valloc, (3) posix_memalign, (4) memalign, or (5) aligned_alloc functions. ..read more

Stack-based buffer overflow in the getaddrinfo function in sysdeps/posix/getaddrinfo.c in GNU C Library (aka glibc or libc6) 2.18 and earlier allows remote attackers to cause a denial of service (crash) via a (1) hostname or (2) IP address that triggers a large number of AF_INET6 address results. NOTE: this vulnerability exists because of an incomplete fix for CVE-2013-1914. ..read more

The PTR_MANGLE implementation in the GNU C Library (aka glibc or libc6) 2.4, 2.17, and earlier, and Embedded GLIBC (EGLIBC) does not initialize the random value for the pointer guard, which makes it easier for context-dependent attackers to control execution flow by leveraging a buffer-overflow vulnerability in an application and using the known zero value pointer guard to calculate a pointer address. ..read more

The send_dg function in resolv/res_send.c in GNU C Library (aka glibc or libc6) before 2.20 does not properly reuse file descriptors, which allows remote attackers to send DNS queries to unintended locations via a large number of requests that trigger a call to the getaddrinfo function. ..read more

The getaddrinfo function in glibc before 2.15, when compiled with libidn and the AI_IDN flag is used, allows context-dependent attackers to cause a denial of service (invalid free) and possibly execute arbitrary code via unspecified vectors, as demonstrated by an internationalized domain name to ping6. ..read more

Multiple directory traversal vulnerabilities in GNU C Library (aka glibc or libc6) before 2.20 allow context-dependent attackers to bypass ForceCommand restrictions and possibly have other unspecified impact via a .. (dot dot) in a (1) LC_*, (2) LANG, or other locale environment variable. ..read more

The posix_spawn_file_actions_addopen function in glibc before 2.20 does not copy its path argument in accordance with the POSIX specification, which allows context-dependent attackers to trigger use-after-free vulnerabilities. ..read more

Off-by-one error in the __gconv_translit_find function in gconv_trans.c in GNU C Library (aka glibc) allows context-dependent attackers to cause a denial of service (crash) or execute arbitrary code via vectors related to the CHARSET environment variable and gconv transliteration modules. ..read more

GNU C Library (aka glibc) before 2.20 allows context-dependent attackers to cause a denial of service (out-of-bounds read and crash) via a multibyte character value of "0xffff" to the iconv function when converting (1) IBM933, (2) IBM935, (3) IBM937, (4) IBM939, or (5) IBM1364 encoded data to UTF-8. ..read more

DB_LOOKUP in nss_files/files-XXX.c in the Name Service Switch (NSS) in GNU C Library (aka glibc or libc6) 2.21 and earlier does not properly check if a file is open, which allows remote attackers to cause a denial of service (infinite loop) by performing a look-up on a database while iterating over it, which triggers the file pointer to be reset. ..read more

The nss_dns implementation of getnetbyname in GNU C Library (aka glibc) before 2.21, when the DNS backend in the Name Service Switch configuration is enabled, allows remote attackers to cause a denial of service (infinite loop) by sending a positive answer while a network name is being process. ..read more

Multiple stack-based buffer overflows in the GNU C Library (aka glibc or libc6) before 2.23 allow context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a long argument to the (1) nan, (2) nanf, or (3) nanl function. ..read more

nscd in the GNU C Library (aka glibc or libc6) before version 2.20 does not correctly compute the size of an internal buffer when processing netgroup requests, possibly leading to an nscd daemon crash or code execution as the user running nscd. ..read more

Heap-based buffer overflow in the __nss_hostname_digits_dots function in glibc 2.2, and other 2.x versions before 2.18, allows context-dependent attackers to execute arbitrary code via vectors related to the (1) gethostbyname or (2) gethostbyname2 function, aka "GHOST." ..read more

The ADDW macro in stdio-common/vfscanf.c in the GNU C Library (aka glibc or libc6) before 2.21 does not properly consider data-type size during memory allocation, which allows context-dependent attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact via a long line containing wide characters that are improperly handled in a wscanf call. ..read more

The ADDW macro in stdio-common/vfscanf.c in the GNU C Library (aka glibc or libc6) before 2.21 does not properly consider data-type size during a risk-management decision for use of the alloca function, which might allow context-dependent attackers to cause a denial of service (segmentation violation) or overwrite memory locations beyond the stack boundary via a long line containing wide characters that are improperly handled in a wscanf call. ..read more

Buffer overflow in the gethostbyname_r and other unspecified NSS functions in the GNU C Library (aka glibc or libc6) before 2.22 allows context-dependent attackers to cause a denial of service (crash) or execute arbitrary code via a crafted DNS response, which triggers a call with a misaligned buffer. ..read more

res_query in libresolv in glibc before 2.25 allows remote attackers to cause a denial of service (NULL pointer dereference and process crash). ..read more

The get_contents function in nss_files/files-XXX.c in the Name Service Switch (NSS) in GNU C Library (aka glibc or libc6) before 2.20 might allow local users to cause a denial of service (heap corruption) or gain privileges via a long line in the NSS files database. ..read more

The strftime function in the GNU C Library (aka glibc or libc6) before 2.23 allows context-dependent attackers to cause a denial of service (application crash) or possibly obtain sensitive information via an out-of-range time value. ..read more

The process_envvars function in elf/rtld.c in the GNU C Library (aka glibc or libc6) before 2.23 allows local users to bypass a pointer-guarding protection mechanism via a zero value of the LD_POINTER_GUARD environment variable. ..read more

Integer overflow in the GNU C Library (aka glibc or libc6) before 2.23 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via the size argument to the __hcreate_r function, which triggers out-of-bounds heap-memory access. ..read more

Stack-based buffer overflow in the catopen function in the GNU C Library (aka glibc or libc6) before 2.23 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a long catalog name. ..read more

Integer overflow in the strxfrm function in the GNU C Library (aka glibc or libc6) before 2.21 allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via a long string, which triggers a stack-based buffer overflow. ..read more

Integer overflow in the _IO_wstr_overflow function in libio/wstrops.c in the GNU C Library (aka glibc or libc6) before 2.22 allows context-dependent attackers to cause a denial of service (application crash) or possibly execute arbitrary code via vectors related to computing a size in bytes, which triggers a heap-based buffer overflow. ..read more

The fnmatch function in the GNU C Library (aka glibc or libc6) before 2.22 might allow context-dependent attackers to cause a denial of service (application crash) via a malformed pattern, which triggers an out-of-bounds read. ..read more

The pop_fail_stack function in the GNU C Library (aka glibc or libc6) allows context-dependent attackers to cause a denial of service (assertion failure and application crash) via vectors related to extended regular expression processing. ..read more

The iconv program in the GNU C Library (aka glibc or libc6) 2.31 and earlier, when invoked with multiple suffixes in the destination encoding (TRANSLATE or IGNORE) along with the -c option, enters an infinite loop when processing invalid multi-byte input sequences, leading to a denial of service. ..read more

In the GNU C Library (aka glibc or libc6) through 2.28, the getaddrinfo function would successfully parse a string that contained an IPv4 address followed by whitespace and arbitrary characters, which could lead applications to incorrectly assume that it had parsed a valid string, without the possibility of embedded HTTP headers or other potentially dangerous substrings. ..read more

Stack-based buffer overflow in the glob implementation in GNU C Library (aka glibc) before 2.24, when GLOB_ALTDIRFUNC is used, allows context-dependent attackers to cause a denial of service (crash) via a long name. ..read more

pt_chown in the glibc package before 2.19-18+deb8u4 on Debian jessie; the elibc package before 2.15-0ubuntu10.14 on Ubuntu 12.04 LTS and before 2.19-0ubuntu6.8 on Ubuntu 14.04 LTS; and the glibc package before 2.21-0ubuntu4.2 on Ubuntu 15.10 and before 2.23-0ubuntu1 on Ubuntu 16.04 LTS and 16.10 lacks a namespace check associated with file-descriptor passing, which allows local users to capture keystrokes and spoof data, and possibly gain privileges, via pts read and write operations, related to debian/sysdeps/linux.mk. NOTE: this is not considered a vulnerability in the upstream GNU C Library because the upstream documentation has a clear security recommendation against the --enable-pt_chown option. ..read more

Stack-based buffer overflow in the nss_dns implementation of the getnetbyname function in GNU C Library (aka glibc) before 2.24 allows context-dependent attackers to cause a denial of service (stack consumption and application crash) via a long name. ..read more

Stack-based buffer overflow in the getaddrinfo function in sysdeps/posix/getaddrinfo.c in the GNU C Library (aka glibc or libc6) allows remote attackers to cause a denial of service (crash) via vectors involving hostent conversion. NOTE: this vulnerability exists because of an incomplete fix for CVE-2013-4458. ..read more

Memory leak in the __res_vinit function in the IPv6 name server management code in libresolv in GNU C Library (aka glibc or libc6) before 2.24 allows remote attackers to cause a denial of service (memory consumption) by leveraging partial initialization of internal resolver data structures. ..read more

The makecontext function in the GNU C Library (aka glibc or libc6) before 2.25 creates execution contexts incompatible with the unwinder on ARM EABI (32-bit) platforms, which might allow context-dependent attackers to cause a denial of service (hang), as demonstrated by applications compiled using gccgo, related to backtrace generation. ..read more

glibc contains a vulnerability that allows specially crafted LD_LIBRARY_PATH values to manipulate the heap/stack, causing them to alias, potentially resulting in arbitrary code execution. Please note that additional hardening changes have been made to glibc to prevent manipulation of stack and heap memory but these issues are not directly exploitable, as such they have not been given a CVE. This affects glibc 2.25 and earlier. ..read more

The DNS stub resolver in the GNU C Library (aka glibc or libc6) before version 2.26, when EDNS support is enabled, will solicit large UDP responses from name servers, potentially simplifying off-path DNS spoofing attacks due to IP fragmentation. ..read more

Use-after-free vulnerability in the clntudp_call function in sunrpc/clnt_udp.c in the GNU C Library (aka glibc or libc6) before 2.26 allows remote attackers to have unspecified impact via vectors related to error path. ..read more

The GNU C Library (aka glibc or libc6) before 2.27 contains an off-by-one error leading to a heap-based buffer overflow in the glob function in glob.c, related to the processing of home directories using the ~ operator followed by a long string. ..read more

The glob function in glob.c in the GNU C Library (aka glibc or libc6) before 2.27, when invoked with GLOB_TILDE, could skip freeing allocated memory when processing the ~ operator with a long user name, potentially leading to a denial of service (memory leak). ..read more

The glob function in glob.c in the GNU C Library (aka glibc or libc6) before 2.27 contains a buffer overflow during unescaping of user names with the ~ operator. ..read more

In glibc 2.26 and earlier there is confusion in the usage of getcwd() by realpath() which can be used to write before the destination buffer leading to a buffer underflow and potential code execution. ..read more

stdlib/canonicalize.c in the GNU C Library (aka glibc or libc6) 2.27 and earlier, when processing very long pathname arguments to the realpath function, could encounter an integer overflow on 32-bit architectures, leading to a stack-based buffer overflow and, potentially, arbitrary code execution. ..read more

An AVX-512-optimized implementation of the mempcpy function in the GNU C Library (aka glibc or libc6) 2.27 and earlier may write data beyond the target buffer, leading to a buffer overflow in __mempcpy_avx512_no_vzeroupper. ..read more

In the GNU C Library (aka glibc or libc6) through 2.28, attempting to resolve a crafted hostname via getaddrinfo() leads to the allocation of a socket descriptor that is not closed. This is related to the if_nametoindex() function. ..read more

In the GNU C Library (aka glibc or libc6) through 2.29, check_dst_limits_calc_pos_1 in posix/regexec.c has Uncontrolled Recursion, as demonstrated by '(\227|)(\\1\\1|t1|\\\2537)+' in grep. ..read more

An integer overflow in the implementation of the posix_memalign in memalign functions in the GNU C Library (aka glibc or libc6) 2.26 and earlier could cause these functions to return a pointer to a heap area that is too small, potentially leading to heap corruption. ..read more

On the x86-64 architecture, the GNU C Library (aka glibc) before 2.31 fails to ignore the LD_PREFER_MAP_32BIT_EXEC environment variable during program execution after a security transition, allowing local attackers to restrict the possible mapping addresses for loaded libraries and thus bypass ASLR for a setuid program. ..read more

The iconv feature in the GNU C Library (aka glibc or libc6) through 2.32, when processing invalid multi-byte input sequences in the EUC-KR encoding, may have a buffer over-read. ..read more

The string component in the GNU C Library (aka glibc or libc6) through 2.28, when running on the x32 architecture, incorrectly attempts to use a 64-bit register for size_t in assembly codes, which can lead to a segmentation fault or possibly unspecified other impact, as demonstrated by a crash in __memmove_avx_unaligned_erms in sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S during a memcpy. ..read more

In the GNU C Library (aka glibc or libc6) through 2.29, the memcmp function for the x32 architecture can incorrectly return zero (indicating that the inputs are equal) because the RDX most significant bit is mishandled. ..read more

In the GNU C Library (aka glibc or libc6) through 2.29, proceed_next_node in posix/regexec.c has a heap-based buffer over-read via an attempted case-insensitive regular-expression match. ..read more

** DISPUTED ** In the GNU C Library (aka glibc or libc6) through 2.29, check_dst_limits_calc_pos_1 in posix/regexec.c has Uncontrolled Recursion, as demonstrated by '(|)(\\1\\1)*' in grep, a different issue than CVE-2018-20796. NOTE: the software maintainer disputes that this is a vulnerability because the behavior occurs only with a crafted pattern. ..read more

The GNU C Library (aka glibc or libc6) before 2.32 could overflow an on-stack buffer during range reduction if an input to an 80-bit long double function contains a non-canonical bit pattern, a seen when passing a 0x5d414141414141410000 value to sinl on x86 targets. This is related to sysdeps/ieee754/ldbl-96/e_rem_pio2l.c. ..read more

An out-of-bounds write vulnerability was found in glibc before 2.31 when handling signal trampolines on PowerPC. Specifically, the backtrace function did not properly check the array bounds when storing the frame address, resulting in a denial of service or potential code execution. The highest threat from this vulnerability is to system availability. ..read more

A use-after-free vulnerability introduced in glibc upstream version 2.14 was found in the way the tilde expansion was carried out. Directory paths containing an initial tilde followed by a valid username were affected by this issue. A local attacker could exploit this flaw by creating a specially crafted path that, when processed by the glob function, would potentially lead to arbitrary code execution. This was fixed in version 2.32. ..read more

The iconv function in the GNU C Library (aka glibc or libc6) 2.32 and earlier, when processing invalid multi-byte input sequences in IBM1364, IBM1371, IBM1388, IBM1390, and IBM1399 encodings, fails to advance the input state, which could lead to an infinite loop in applications, resulting in a denial of service, a different vulnerability from CVE-2016-10228. ..read more

sysdeps/i386/ldbl2mpn.c in the GNU C Library (aka glibc or libc6) before 2.23 on x86 targets has a stack-based buffer overflow if the input to any of the printf family of functions is an 80-bit long double with a non-canonical bit pattern, as seen when passing a \x00\x04\x00\x00\x00\x00\x00\x00\x00\x04 value to sprintf. NOTE: the issue does not affect glibc by default in 2016 or later (i.e., 2.23 or later) because of commits made in 2015 for inlining of C99 math functions through use of GCC built-ins. In other words, the reference to 2.23 is intentional despite the mention of "Fixed for glibc 2.33" in the 26649 reference. ..read more

An exploitable signed comparison vulnerability exists in the ARMv7 memcpy() implementation of GNU glibc 2.30.9000. Calling memcpy() (on ARMv7 targets that utilize the GNU glibc implementation) with a negative value for the 'num' parameter results in a signed comparison vulnerability. If an attacker underflows the 'num' parameter to memcpy(), this vulnerability could lead to undefined behavior such as writing to out-of-bounds memory and potentially remote code execution. Furthermore, this memcpy() implementation allows for program execution to continue in scenarios where a segmentation fault or crash should have occurred. The dangers occur in that subsequent execution and iterations of this code will be executed with this corrupted data. ..read more

The iconv function in the GNU C Library (aka glibc or libc6) 2.32 and earlier, when processing invalid input sequences in the ISO-2022-JP-3 encoding, fails an assertion in the code path and aborts the program, potentially resulting in a denial of service. ..read more

The wordexp function in the GNU C Library (aka glibc) through 2.33 may crash or read arbitrary memory in parse_param (in posix/wordexp.c) when called with an untrusted, crafted pattern, potentially resulting in a denial of service or disclosure of information. This occurs because atoi was used but strtoul should have been used to ensure correct calculations. ..read more

In librt in the GNU C Library (aka glibc) through 2.34, sysdeps/unix/sysv/linux/mq_notify.c mishandles certain NOTIFY_REMOVED data, leading to a NULL pointer dereference. NOTE: this vulnerability was introduced as a side effect of the CVE-2021-33574 fix. ..read more

A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input buffer and size passed to getcwd() in a setuid program could use this flaw to potentially execute arbitrary code and escalate their privileges on the system. ..read more

The deprecated compatibility function svcunix_create in the sunrpc module of the GNU C Library (aka glibc) through 2.34 copies its path argument on the stack without validating its length, which may result in a buffer overflow, potentially resulting in a denial of service or (if an application is not built with a stack protector enabled) arbitrary code execution. ..read more

The deprecated compatibility function clnt_create in the sunrpc module of the GNU C Library (aka glibc) through 2.34 copies its hostname argument on the stack without validating its length, which may result in a buffer overflow, potentially resulting in a denial of service or (if an application is not built with a stack protector enabled) arbitrary code execution. ..read more

The glob implementation in the GNU C Library (aka glibc or libc6) allows remote authenticated users to cause a denial of service (CPU and memory consumption) via crafted glob expressions that do not match any pathnames, as demonstrated by glob expressions in STAT commands to an FTP daemon, a different vulnerability than CVE-2010-2632. ..read more

slim has NULL pointer dereference when using crypt() method from glibc 2.17 ..read more

In the GNU C Library (aka glibc or libc6) through 2.29, check_dst_limits_calc_pos_1 in posix/regexec.c has Uncontrolled Recursion, as demonstrated by '(\227|)(\\1\\1|t1|\\\2537)+' in grep. ..read more

On the x86-64 architecture, the GNU C Library (aka glibc) before 2.31 fails to ignore the LD_PREFER_MAP_32BIT_EXEC environment variable during program execution after a security transition, allowing local attackers to restrict the possible mapping addresses for loaded libraries and thus bypass ASLR for a setuid program. ..read more

The iconv feature in the GNU C Library (aka glibc or libc6) through 2.32, when processing invalid multi-byte input sequences in the EUC-KR encoding, may have a buffer over-read. ..read more

In the GNU C Library (aka glibc or libc6) through 2.29, the memcmp function for the x32 architecture can incorrectly return zero (indicating that the inputs are equal) because the RDX most significant bit is mishandled. ..read more

In the GNU C Library (aka glibc or libc6) through 2.29, proceed_next_node in posix/regexec.c has a heap-based buffer over-read via an attempted case-insensitive regular-expression match. ..read more

** DISPUTED ** In the GNU C Library (aka glibc or libc6) through 2.29, check_dst_limits_calc_pos_1 in posix/regexec.c has Uncontrolled Recursion, as demonstrated by '(|)(\\1\\1)*' in grep, a different issue than CVE-2018-20796. NOTE: the software maintainer disputes that this is a vulnerability because the behavior occurs only with a crafted pattern. ..read more

The GNU C Library (aka glibc or libc6) before 2.32 could overflow an on-stack buffer during range reduction if an input to an 80-bit long double function contains a non-canonical bit pattern, a seen when passing a 0x5d414141414141410000 value to sinl on x86 targets. This is related to sysdeps/ieee754/ldbl-96/e_rem_pio2l.c. ..read more

An out-of-bounds write vulnerability was found in glibc before 2.31 when handling signal trampolines on PowerPC. Specifically, the backtrace function did not properly check the array bounds when storing the frame address, resulting in a denial of service or potential code execution. The highest threat from this vulnerability is to system availability. ..read more

A use-after-free vulnerability introduced in glibc upstream version 2.14 was found in the way the tilde expansion was carried out. Directory paths containing an initial tilde followed by a valid username were affected by this issue. A local attacker could exploit this flaw by creating a specially crafted path that, when processed by the glob function, would potentially lead to arbitrary code execution. This was fixed in version 2.32. ..read more

The iconv function in the GNU C Library (aka glibc or libc6) 2.32 and earlier, when processing invalid multi-byte input sequences in IBM1364, IBM1371, IBM1388, IBM1390, and IBM1399 encodings, fails to advance the input state, which could lead to an infinite loop in applications, resulting in a denial of service, a different vulnerability from CVE-2016-10228. ..read more

An exploitable signed comparison vulnerability exists in the ARMv7 memcpy() implementation of GNU glibc 2.30.9000. Calling memcpy() (on ARMv7 targets that utilize the GNU glibc implementation) with a negative value for the 'num' parameter results in a signed comparison vulnerability. If an attacker underflows the 'num' parameter to memcpy(), this vulnerability could lead to undefined behavior such as writing to out-of-bounds memory and potentially remote code execution. Furthermore, this memcpy() implementation allows for program execution to continue in scenarios where a segmentation fault or crash should have occurred. The dangers occur in that subsequent execution and iterations of this code will be executed with this corrupted data. ..read more

The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6) 2.29 through 2.33, when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system. This is related to netgroupcache.c. ..read more

The iconv function in the GNU C Library (aka glibc or libc6) 2.32 and earlier, when processing invalid input sequences in the ISO-2022-JP-3 encoding, fails an assertion in the code path and aborts the program, potentially resulting in a denial of service. ..read more

The wordexp function in the GNU C Library (aka glibc) through 2.33 may crash or read arbitrary memory in parse_param (in posix/wordexp.c) when called with an untrusted, crafted pattern, potentially resulting in a denial of service or disclosure of information. This occurs because atoi was used but strtoul should have been used to ensure correct calculations. ..read more

In librt in the GNU C Library (aka glibc) through 2.34, sysdeps/unix/sysv/linux/mq_notify.c mishandles certain NOTIFY_REMOVED data, leading to a NULL pointer dereference. NOTE: this vulnerability was introduced as a side effect of the CVE-2021-33574 fix. ..read more

A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input buffer and size passed to getcwd() in a setuid program could use this flaw to potentially execute arbitrary code and escalate their privileges on the system. ..read more

The deprecated compatibility function svcunix_create in the sunrpc module of the GNU C Library (aka glibc) through 2.34 copies its path argument on the stack without validating its length, which may result in a buffer overflow, potentially resulting in a denial of service or (if an application is not built with a stack protector enabled) arbitrary code execution. ..read more

The deprecated compatibility function clnt_create in the sunrpc module of the GNU C Library (aka glibc) through 2.34 copies its hostname argument on the stack without validating its length, which may result in a buffer overflow, potentially resulting in a denial of service or (if an application is not built with a stack protector enabled) arbitrary code execution. ..read more

zlib through 1.2.12 has a heap-based buffer over-read or buffer overflow in inflate in inflate.c via a large gzip header extra field. NOTE: only applications that call inflateGetHeader are affected. Some common applications bundle the affected zlib source code but may be unable to call inflateGetHeader (e.g., see the nodejs/node reference). ..read more

Mutt 1.5.19, when linked against (1) OpenSSL (mutt_ssl.c) or (2) GnuTLS (mutt_ssl_gnutls.c), allows connections when only one TLS certificate in the chain is accepted instead of verifying the entire chain, which allows remote attackers to spoof trusted servers via a man-in-the-middle attack. ..read more

mutt_ssl.c in mutt 1.5.19 and 1.5.20, when OpenSSL is used, does not properly handle a '\0' character in a domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408. ..read more

mutt_ssl.c in mutt 1.5.16 and other versions before 1.5.19, when OpenSSL is used, does not verify the domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate. ..read more

The ssl3_get_key_exchange function in ssl/s3_clnt.c in OpenSSL 1.0.2 before 1.0.2e allows remote servers to cause a denial of service (segmentation fault) via a zero p value in an anonymous Diffie-Hellman (DH) ServerKeyExchange message. ..read more

The Montgomery squaring implementation in crypto/bn/asm/x86_64-mont5.pl in OpenSSL 1.0.2 before 1.0.2e on the x86_64 platform, as used by the BN_mod_exp function, mishandles carry propagation and produces incorrect output, which makes it easier for remote attackers to obtain sensitive private-key information via an attack against use of a (1) Diffie-Hellman (DH) or (2) Diffie-Hellman Ephemeral (DHE) ciphersuite. ..read more

crypto/rsa/rsa_ameth.c in OpenSSL 1.0.1 before 1.0.1q and 1.0.2 before 1.0.2e allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via an RSA PSS ASN.1 signature that lacks a mask generation function parameter. ..read more

The ASN1_TFLG_COMBINE implementation in crypto/asn1/tasn_dec.c in OpenSSL before 0.9.8zh, 1.0.0 before 1.0.0t, 1.0.1 before 1.0.1q, and 1.0.2 before 1.0.2e mishandles errors caused by malformed X509_ATTRIBUTE data, which allows remote attackers to obtain sensitive information from process memory by triggering a decoding failure in a PKCS#7 or CMS application. ..read more

ssl/s2_srvr.c in OpenSSL 1.0.1 before 1.0.1r and 1.0.2 before 1.0.2f does not prevent use of disabled ciphers, which makes it easier for man-in-the-middle attackers to defeat cryptographic protection mechanisms by performing computations on SSLv2 traffic, related to the get_client_master_key and get_client_hello functions. ..read more

The DH_check_pub_key function in crypto/dh/dh_check.c in OpenSSL 1.0.2 before 1.0.2f does not ensure that prime numbers are appropriate for Diffie-Hellman (DH) key exchange, which makes it easier for remote attackers to discover a private DH exponent by making multiple handshakes with a peer that chose an inappropriate number, as demonstrated by a number in an X9.42 file. ..read more

The MOD_EXP_CTIME_COPY_FROM_PREBUF function in crypto/bn/bn_exp.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g does not properly consider cache-bank access times during modular exponentiation, which makes it easier for local users to discover RSA keys by running a crafted application on the same Intel Sandy Bridge CPU core as a victim and leveraging cache-bank conflicts, aka a "CacheBleed" attack. ..read more

Double free vulnerability in the dsa_priv_decode function in crypto/dsa/dsa_ameth.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g allows remote attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact via a malformed DSA private key. ..read more

Multiple integer overflows in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g allow remote attackers to cause a denial of service (heap memory corruption or NULL pointer dereference) or possibly have unspecified other impact via a long digit string that is mishandled by the (1) BN_dec2bn or (2) BN_hex2bn function, related to crypto/bn/bn.h and crypto/bn/bn_print.c. ..read more

Memory leak in the SRP_VBASE_get_by_user implementation in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g allows remote attackers to cause a denial of service (memory consumption) by providing an invalid username in a connection attempt, related to apps/s_server.c and crypto/srp/srp_vfy.c. ..read more

The fmtstr function in crypto/bio/b_print.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g improperly calculates string lengths, which allows remote attackers to cause a denial of service (overflow and out-of-bounds read) or possibly have unspecified other impact via a long string, as demonstrated by a large amount of ASN.1 data, a different vulnerability than CVE-2016-2842. ..read more

The SSLv2 protocol, as used in OpenSSL before 1.0.1s and 1.0.2 before 1.0.2g and other products, requires a server to send a ServerVerify message before establishing that a client possesses certain plaintext RSA data, which makes it easier for remote attackers to decrypt TLS ciphertext data by leveraging a Bleichenbacher RSA padding oracle, aka a "DROWN" attack. ..read more

Integer overflow in the EVP_EncodeUpdate function in crypto/evp/encode.c in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to cause a denial of service (heap memory corruption) via a large amount of binary data. ..read more

Integer overflow in the EVP_EncryptUpdate function in crypto/evp/evp_enc.c in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to cause a denial of service (heap memory corruption) via a large amount of data. ..read more

The AES-NI implementation in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h does not consider memory allocation during a certain padding check, which allows remote attackers to obtain sensitive cleartext information via a padding-oracle attack against an AES CBC session. NOTE: this vulnerability exists because of an incorrect fix for CVE-2013-0169. ..read more

The asn1_d2i_read_bio function in crypto/asn1/a_d2i_fp.c in the ASN.1 BIO implementation in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to cause a denial of service (memory consumption) via a short invalid encoding. ..read more

The X509_NAME_oneline function in crypto/x509/x509_obj.c in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to obtain sensitive information from process stack memory or cause a denial of service (buffer over-read) via crafted EBCDIC ASN.1 data. ..read more

OpenSSL through 1.0.2h incorrectly uses pointer arithmetic for heap-buffer boundary checks, which might allow remote attackers to cause a denial of service (integer overflow and application crash) or possibly have unspecified other impact by leveraging unexpected malloc behavior, related to s3_srvr.c, ssl_sess.c, and t1_lib.c. ..read more

The dsa_sign_setup function in crypto/dsa/dsa_ossl.c in OpenSSL through 1.0.2h does not properly ensure the use of constant-time operations, which makes it easier for local users to discover a DSA private key via a timing side-channel attack. ..read more

The DTLS implementation in OpenSSL before 1.1.0 does not properly restrict the lifetime of queue entries associated with unused out-of-order messages, which allows remote attackers to cause a denial of service (memory consumption) by maintaining many crafted DTLS sessions simultaneously, related to d1_lib.c, statem_dtls.c, statem_lib.c, and statem_srvr.c. ..read more

The TS_OBJ_print_bio function in crypto/ts/ts_lib.c in the X.509 Public Key Infrastructure Time-Stamp Protocol (TSP) implementation in OpenSSL through 1.0.2h allows remote attackers to cause a denial of service (out-of-bounds read and application crash) via a crafted time-stamp file that is mishandled by the "openssl ts" command. ..read more

The Anti-Replay feature in the DTLS implementation in OpenSSL before 1.1.0 mishandles early use of a new epoch number in conjunction with a large sequence number, which allows remote attackers to cause a denial of service (false-positive packet drops) via spoofed DTLS records, related to rec_layer_d1.c and ssl3_record.c. ..read more

The BN_bn2dec function in crypto/bn/bn_print.c in OpenSSL before 1.1.0 does not properly validate division results, which allows remote attackers to cause a denial of service (out-of-bounds write and application crash) or possibly have unspecified other impact via unknown vectors. ..read more

The DES and Triple DES ciphers, as used in the TLS, SSH, and IPSec protocols and other protocols and products, have a birthday bound of approximately four billion blocks, which makes it easier for remote attackers to obtain cleartext data via a birthday attack against a long-duration encrypted session, as demonstrated by an HTTPS session using Triple DES in CBC mode, aka a "Sweet32" attack. ..read more

The doapr_outch function in crypto/bio/b_print.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g does not verify that a certain memory allocation succeeds, which allows remote attackers to cause a denial of service (out-of-bounds write or memory consumption) or possibly have unspecified other impact via a long string, as demonstrated by a large amount of ASN.1 data, a different vulnerability than CVE-2016-0799. ..read more

The tls_decrypt_ticket function in ssl/t1_lib.c in OpenSSL before 1.1.0 does not consider the HMAC size during validation of the ticket length, which allows remote attackers to cause a denial of service via a ticket that is too short. ..read more

Integer overflow in the MDC2_Update function in crypto/mdc2/mdc2dgst.c in OpenSSL before 1.1.0 allows remote attackers to cause a denial of service (out-of-bounds write and application crash) or possibly have unspecified other impact via unknown vectors. ..read more

Multiple memory leaks in t1_lib.c in OpenSSL before 1.0.1u, 1.0.2 before 1.0.2i, and 1.1.0 before 1.1.0a allow remote attackers to cause a denial of service (memory consumption) via large OCSP Status Request extensions. ..read more

The certificate parser in OpenSSL before 1.0.1u and 1.0.2 before 1.0.2i might allow remote attackers to cause a denial of service (out-of-bounds read) via crafted certificate operations, related to s3_clnt.c and s3_srvr.c. ..read more

There is a carry propagating bug in the Broadwell-specific Montgomery multiplication procedure in OpenSSL 1.0.2 and 1.1.0 before 1.1.0c that handles input lengths divisible by, but longer than 256 bits. Analysis suggests that attacks against RSA, DSA and DH private keys are impossible. This is because the subroutine in question is not used in operations with the private key itself and an input of the attacker's direct choice. Otherwise the bug can manifest itself as transient authentication and key negotiation failures or reproducible erroneous outcome of public-key operations with specially crafted input. Among EC algorithms only Brainpool P-512 curves are affected and one presumably can attack ECDH key negotiation. Impact was not analyzed in detail, because pre-requisites for attack are considered unlikely. Namely multiple clients have to choose the curve in question and the server has to share the private key among them, neither of which is default behaviour. Even then only clients that chose the curve will be affected. ..read more

A denial of service flaw was found in OpenSSL 0.9.8, 1.0.1, 1.0.2 through 1.0.2h, and 1.1.0 in the way the TLS/SSL protocol defined processing of ALERT packets during a connection handshake. A remote attacker could use this flaw to make a TLS/SSL server consume an excessive amount of CPU and fail to accept connections from other clients. ..read more

If an SSL/TLS server or client is running on a 32-bit host, and a specific cipher is being used, then a truncated packet can cause that server or client to perform an out-of-bounds read, usually resulting in a crash. For OpenSSL 1.1.0, the crash can be triggered when using CHACHA20/POLY1305; users should upgrade to 1.1.0d. For Openssl 1.0.2, the crash can be triggered when using RC4-MD5; users who have not disabled that algorithm should update to 1.0.2k. ..read more

There is a carry propagating bug in the x86_64 Montgomery squaring procedure in OpenSSL 1.0.2 before 1.0.2k and 1.1.0 before 1.1.0d. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. For example this can occur by default in OpenSSL DHE based SSL/TLS ciphersuites. Note: This issue is very similar to CVE-2015-3193 but must be treated as a separate problem. ..read more

While parsing an IPAddressFamily extension in an X.509 certificate, it is possible to do a one-byte overread. This would result in an incorrect text display of the certificate. This bug has been present since 2006 and is present in all versions of OpenSSL before 1.0.2m and 1.1.0g. ..read more

There is a carry propagating bug in the x86_64 Montgomery squaring procedure in OpenSSL before 1.0.2m and 1.1.0 before 1.1.0g. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. This only affects processors that support the BMI1, BMI2 and ADX extensions like Intel Broadwell (5th generation) and later or AMD Ryzen. ..read more

OpenSSL 1.0.2 (starting from version 1.0.2b) introduced an "error state" mechanism. The intent was that if a fatal error occurred during a handshake then OpenSSL would move into the error state and would immediately fail if you attempted to continue the handshake. This works as designed for the explicit handshake functions (SSL_do_handshake(), SSL_accept() and SSL_connect()), however due to a bug it does not work correctly if SSL_read() or SSL_write() is called directly. In that scenario, if the handshake fails then a fatal error will be returned in the initial function call. If SSL_read()/SSL_write() is subsequently called by the application for the same SSL object then it will succeed and the data is passed without being decrypted/encrypted directly from the SSL/TLS record layer. In order to exploit this issue an application bug would have to be present that resulted in a call to SSL_read()/SSL_write() being issued after having already received a fatal error. OpenSSL version 1.0.2b-1.0.2m are affected. Fixed in OpenSSL 1.0.2n. OpenSSL 1.1.0 is not affected. ..read more

There is an overflow bug in the AVX2 Montgomery multiplication procedure used in exponentiation with 1024-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH1024 are considered just feasible, because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be significant. However, for an attack on TLS to be meaningful, the server would have to share the DH1024 private key among multiple clients, which is no longer an option since CVE-2016-0701. This only affects processors that support the AVX2 but not ADX extensions like Intel Haswell (4th generation). Note: The impact from this issue is similar to CVE-2017-3736, CVE-2017-3732 and CVE-2015-3193. OpenSSL version 1.0.2-1.0.2m and 1.1.0-1.1.0g are affected. Fixed in OpenSSL 1.0.2n. Due to the low severity of this issue we are not issuing a new release of OpenSSL 1.1.0 at this time. The fix will be included in OpenSSL 1.1.0h when it becomes available. The fix is also available in commit e502cc86d in the OpenSSL git repository. ..read more

The OpenSSL RSA Key generation algorithm has been shown to be vulnerable to a cache timing side channel attack. An attacker with sufficient access to mount cache timing attacks during the RSA key generation process could recover the private key. Fixed in OpenSSL 1.1.0i-dev (Affected 1.1.0-1.1.0h). Fixed in OpenSSL 1.0.2p-dev (Affected 1.0.2b-1.0.2o). ..read more

Constructed ASN.1 types with a recursive definition (such as can be found in PKCS7) could eventually exceed the stack given malicious input with excessive recursion. This could result in a Denial Of Service attack. There are no such structures used within SSL/TLS that come from untrusted sources so this is considered safe. Fixed in OpenSSL 1.1.0h (Affected 1.1.0-1.1.0g). Fixed in OpenSSL 1.0.2o (Affected 1.0.2b-1.0.2n). ..read more

Simultaneous Multi-threading (SMT) in processors can enable local users to exploit software vulnerable to timing attacks via a side-channel timing attack on 'port contention'. ..read more

Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s). ..read more

There is an overflow bug in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME. Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d). Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t). ..read more

OpenSSL has internal defaults for a directory tree where it can find a configuration file as well as certificates used for verification in TLS. This directory is most commonly referred to as OPENSSLDIR, and is configurable with the --prefix / --openssldir configuration options. For OpenSSL versions 1.1.0 and 1.1.1, the mingw configuration targets assume that resulting programs and libraries are installed in a Unix-like environment and the default prefix for program installation as well as for OPENSSLDIR should be '/usr/local'. However, mingw programs are Windows programs, and as such, find themselves looking at sub-directories of 'C:/usr/local', which may be world writable, which enables untrusted users to modify OpenSSL's default configuration, insert CA certificates, modify (or even replace) existing engine modules, etc. For OpenSSL 1.0.2, '/usr/local/ssl' is used as default for OPENSSLDIR on all Unix and Windows targets, including Visual C builds. However, some build instructions for the diverse Windows targets on 1.0.2 encourage you to specify your own --prefix. OpenSSL versions 1.1.1, 1.1.0 and 1.0.2 are affected by this issue. Due to the limited scope of affected deployments this has been assessed as low severity and therefore we are not creating new releases at this time. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s). ..read more

If an application encounters a fatal protocol error and then calls SSL_shutdown() twice (once to send a close_notify, and once to receive one) then OpenSSL can respond differently to the calling application if a 0 byte record is received with invalid padding compared to if a 0 byte record is received with an invalid MAC. If the application then behaves differently based on that in a way that is detectable to the remote peer, then this amounts to a padding oracle that could be used to decrypt data. In order for this to be exploitable "non-stitched" ciphersuites must be in use. Stitched ciphersuites are optimised implementations of certain commonly used ciphersuites. Also the application must call SSL_shutdown() twice even if a protocol error has occurred (applications should not do this but some do anyway). Fixed in OpenSSL 1.0.2r (Affected 1.0.2-1.0.2q). ..read more

In situations where an attacker receives automated notification of the success or failure of a decryption attempt an attacker, after sending a very large number of messages to be decrypted, can recover a CMS/PKCS7 transported encryption key or decrypt any RSA encrypted message that was encrypted with the public RSA key, using a Bleichenbacher padding oracle attack. Applications are not affected if they use a certificate together with the private RSA key to the CMS_decrypt or PKCS7_decrypt functions to select the correct recipient info to decrypt. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s). ..read more

The Raccoon attack exploits a flaw in the TLS specification which can lead to an attacker being able to compute the pre-master secret in connections which have used a Diffie-Hellman (DH) based ciphersuite. In such a case this would result in the attacker being able to eavesdrop on all encrypted communications sent over that TLS connection. The attack can only be exploited if an implementation re-uses a DH secret across multiple TLS connections. Note that this issue only impacts DH ciphersuites and not ECDH ciphersuites. This issue affects OpenSSL 1.0.2 which is out of support and no longer receiving public updates. OpenSSL 1.1.1 is not vulnerable to this issue. Fixed in OpenSSL 1.0.2w (Affected 1.0.2-1.0.2v). ..read more

Calls to EVP_CipherUpdate, EVP_EncryptUpdate and EVP_DecryptUpdate may overflow the output length argument in some cases where the input length is close to the maximum permissable length for an integer on the platform. In such cases the return value from the function call will be 1 (indicating success), but the output length value will be negative. This could cause applications to behave incorrectly or crash. OpenSSL versions 1.1.1i and below are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1j. OpenSSL versions 1.0.2x and below are affected by this issue. However OpenSSL 1.0.2 is out of support and no longer receiving public updates. Premium support customers of OpenSSL 1.0.2 should upgrade to 1.0.2y. Other users should upgrade to 1.1.1j. Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i). Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x). ..read more

The OpenSSL public API function X509_issuer_and_serial_hash() attempts to create a unique hash value based on the issuer and serial number data contained within an X509 certificate. However it fails to correctly handle any errors that may occur while parsing the issuer field (which might occur if the issuer field is maliciously constructed). This may subsequently result in a NULL pointer deref and a crash leading to a potential denial of service attack. The function X509_issuer_and_serial_hash() is never directly called by OpenSSL itself so applications are only vulnerable if they use this function directly and they use it on certificates that may have been obtained from untrusted sources. OpenSSL versions 1.1.1i and below are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1j. OpenSSL versions 1.0.2x and below are affected by this issue. However OpenSSL 1.0.2 is out of support and no longer receiving public updates. Premium support customers of OpenSSL 1.0.2 should upgrade to 1.0.2y. Other users should upgrade to 1.1.1j. Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i). Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x). ..read more

ASN.1 strings are represented internally within OpenSSL as an ASN1_STRING structure which contains a buffer holding the string data and a field holding the buffer length. This contrasts with normal C strings which are repesented as a buffer for the string data which is terminated with a NUL (0) byte. Although not a strict requirement, ASN.1 strings that are parsed using OpenSSL's own "d2i" functions (and other similar parsing functions) as well as any string whose value has been set with the ASN1_STRING_set() function will additionally NUL terminate the byte array in the ASN1_STRING structure. However, it is possible for applications to directly construct valid ASN1_STRING structures which do not NUL terminate the byte array by directly setting the "data" and "length" fields in the ASN1_STRING array. This can also happen by using the ASN1_STRING_set0() function. Numerous OpenSSL functions that print ASN.1 data have been found to assume that the ASN1_STRING byte array will be NUL terminated, even though this is not guaranteed for strings that have been directly constructed. Where an application requests an ASN.1 structure to be printed, and where that ASN.1 structure contains ASN1_STRINGs that have been directly constructed by the application without NUL terminating the "data" field, then a read buffer overrun can occur. The same thing can also occur during name constraints processing of certificates (for example if a certificate has been directly constructed by the application instead of loading it via the OpenSSL parsing functions, and the certificate contains non NUL terminated ASN1_STRING structures). It can also occur in the X509_get1_email(), X509_REQ_get1_email() and X509_get1_ocsp() functions. If a malicious actor can cause an application to directly construct an ASN1_STRING and then process it through one of the affected OpenSSL functions then this issue could be hit. This might result in a crash (causing a Denial of Service attack). It could also result in the disclosure of private memory contents (such as private keys, or sensitive plaintext). Fixed in OpenSSL 1.1.1l (Affected 1.1.1-1.1.1k). Fixed in OpenSSL 1.0.2za (Affected 1.0.2-1.0.2y). ..read more

There is a carry propagation bug in the MIPS32 and MIPS64 squaring procedure. Many EC algorithms are affected, including some of the TLS 1.3 default curves. Impact was not analyzed in detail, because the pre-requisites for attack are considered unlikely and include reusing private keys. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be significant. However, for an attack on TLS to be meaningful, the server would have to share the DH private key among multiple clients, which is no longer an option since CVE-2016-0701. This issue affects OpenSSL versions 1.0.2, 1.1.1 and 3.0.0. It was addressed in the releases of 1.1.1m and 3.0.1 on the 15th of December 2021. For the 1.0.2 release it is addressed in git commit 6fc1aaaf3 that is available to premium support customers only. It will be made available in 1.0.2zc when it is released. The issue only affects OpenSSL on MIPS platforms. Fixed in OpenSSL 3.0.1 (Affected 3.0.0). Fixed in OpenSSL 1.1.1m (Affected 1.1.1-1.1.1l). Fixed in OpenSSL 1.0.2zc-dev (Affected 1.0.2-1.0.2zb). ..read more

The BN_mod_sqrt() function, which computes a modular square root, contains a bug that can cause it to loop forever for non-prime moduli. Internally this function is used when parsing certificates that contain elliptic curve public keys in compressed form or explicit elliptic curve parameters with a base point encoded in compressed form. It is possible to trigger the infinite loop by crafting a certificate that has invalid explicit curve parameters. Since certificate parsing happens prior to verification of the certificate signature, any process that parses an externally supplied certificate may thus be subject to a denial of service attack. The infinite loop can also be reached when parsing crafted private keys as they can contain explicit elliptic curve parameters. Thus vulnerable situations include: - TLS clients consuming server certificates - TLS servers consuming client certificates - Hosting providers taking certificates or private keys from customers - Certificate authorities parsing certification requests from subscribers - Anything else which parses ASN.1 elliptic curve parameters Also any other applications that use the BN_mod_sqrt() where the attacker can control the parameter values are vulnerable to this DoS issue. In the OpenSSL 1.0.2 version the public key is not parsed during initial parsing of the certificate which makes it slightly harder to trigger the infinite loop. However any operation which requires the public key from the certificate will trigger the infinite loop. In particular the attacker can use a self-signed certificate to trigger the loop during verification of the certificate signature. This issue affects OpenSSL versions 1.0.2, 1.1.1 and 3.0. It was addressed in the releases of 1.1.1n and 3.0.2 on the 15th March 2022. Fixed in OpenSSL 3.0.2 (Affected 3.0.0,3.0.1). Fixed in OpenSSL 1.1.1n (Affected 1.1.1-1.1.1m). Fixed in OpenSSL 1.0.2zd (Affected 1.0.2-1.0.2zc). ..read more

The c_rehash script does not properly sanitise shell metacharacters to prevent command injection. This script is distributed by some operating systems in a manner where it is automatically executed. On such operating systems, an attacker could execute arbitrary commands with the privileges of the script. Use of the c_rehash script is considered obsolete and should be replaced by the OpenSSL rehash command line tool. Fixed in OpenSSL 3.0.3 (Affected 3.0.0,3.0.1,3.0.2). Fixed in OpenSSL 1.1.1o (Affected 1.1.1-1.1.1n). Fixed in OpenSSL 1.0.2ze (Affected 1.0.2-1.0.2zd). ..read more

In addition to the c_rehash shell command injection identified in CVE-2022-1292, further circumstances where the c_rehash script does not properly sanitise shell metacharacters to prevent command injection were found by code review. When the CVE-2022-1292 was fixed it was not discovered that there are other places in the script where the file names of certificates being hashed were possibly passed to a command executed through the shell. This script is distributed by some operating systems in a manner where it is automatically executed. On such operating systems, an attacker could execute arbitrary commands with the privileges of the script. Use of the c_rehash script is considered obsolete and should be replaced by the OpenSSL rehash command line tool. Fixed in OpenSSL 3.0.4 (Affected 3.0.0,3.0.1,3.0.2,3.0.3). Fixed in OpenSSL 1.1.1p (Affected 1.1.1-1.1.1o). Fixed in OpenSSL 1.0.2zf (Affected 1.0.2-1.0.2ze). ..read more

A timing based side channel exists in the OpenSSL RSA Decryption implementation which could be sufficient to recover a plaintext across a network in a Bleichenbacher style attack. To achieve a successful decryption an attacker would have to be able to send a very large number of trial messages for decryption. The vulnerability affects all RSA padding modes: PKCS#1 v1.5, RSA-OEAP and RSASVE. For example, in a TLS connection, RSA is commonly used by a client to send an encrypted pre-master secret to the server. An attacker that had observed a genuine connection between a client and a server could use this flaw to send trial messages to the server and record the time taken to process them. After a sufficiently large number of messages the attacker could recover the pre-master secret used for the original connection and thus be able to decrypt the application data sent over that connection. ..read more

The public API function BIO_new_NDEF is a helper function used for streaming ASN.1 data via a BIO. It is primarily used internally to OpenSSL to support the SMIME, CMS and PKCS7 streaming capabilities, but may also be called directly by end user applications. The function receives a BIO from the caller, prepends a new BIO_f_asn1 filter BIO onto the front of it to form a BIO chain, and then returns the new head of the BIO chain to the caller. Under certain conditions, for example if a CMS recipient public key is invalid, the new filter BIO is freed and the function returns a NULL result indicating a failure. However, in this case, the BIO chain is not properly cleaned up and the BIO passed by the caller still retains internal pointers to the previously freed filter BIO. If the caller then goes on to call BIO_pop() on the BIO then a use-after-free will occur. This will most likely result in a crash. This scenario occurs directly in the internal function B64_write_ASN1() which may cause BIO_new_NDEF() to be called and will subsequently call BIO_pop() on the BIO. This internal function is in turn called by the public API functions PEM_write_bio_ASN1_stream, PEM_write_bio_CMS_stream, PEM_write_bio_PKCS7_stream, SMIME_write_ASN1, SMIME_write_CMS and SMIME_write_PKCS7. Other public API functions that may be impacted by this include i2d_ASN1_bio_stream, BIO_new_CMS, BIO_new_PKCS7, i2d_CMS_bio_stream and i2d_PKCS7_bio_stream. The OpenSSL cms and smime command line applications are similarly affected. ..read more

There is a type confusion vulnerability relating to X.400 address processing inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING but the public structure definition for GENERAL_NAME incorrectly specified the type of the x400Address field as ASN1_TYPE. This field is subsequently interpreted by the OpenSSL function GENERAL_NAME_cmp as an ASN1_TYPE rather than an ASN1_STRING. When CRL checking is enabled (i.e. the application sets the X509_V_FLAG_CRL_CHECK flag), this vulnerability may allow an attacker to pass arbitrary pointers to a memcmp call, enabling them to read memory contents or enact a denial of service. In most cases, the attack requires the attacker to provide both the certificate chain and CRL, neither of which need to have a valid signature. If the attacker only controls one of these inputs, the other input must already contain an X.400 address as a CRL distribution point, which is uncommon. As such, this vulnerability is most likely to only affect applications which have implemented their own functionality for retrieving CRLs over a network. ..read more

Mutt 1.5.19, when linked against (1) OpenSSL (mutt_ssl.c) or (2) GnuTLS (mutt_ssl_gnutls.c), allows connections when only one TLS certificate in the chain is accepted instead of verifying the entire chain, which allows remote attackers to spoof trusted servers via a man-in-the-middle attack. ..read more

mutt_ssl.c in mutt 1.5.19 and 1.5.20, when OpenSSL is used, does not properly handle a '\0' character in a domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority, a related issue to CVE-2009-2408. ..read more

mutt_ssl.c in mutt 1.5.16 and other versions before 1.5.19, when OpenSSL is used, does not verify the domain name in the subject's Common Name (CN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate. ..read more

The MOD_EXP_CTIME_COPY_FROM_PREBUF function in crypto/bn/bn_exp.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g does not properly consider cache-bank access times during modular exponentiation, which makes it easier for local users to discover RSA keys by running a crafted application on the same Intel Sandy Bridge CPU core as a victim and leveraging cache-bank conflicts, aka a "CacheBleed" attack. ..read more

Double free vulnerability in the dsa_priv_decode function in crypto/dsa/dsa_ameth.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g allows remote attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact via a malformed DSA private key. ..read more

Multiple integer overflows in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g allow remote attackers to cause a denial of service (heap memory corruption or NULL pointer dereference) or possibly have unspecified other impact via a long digit string that is mishandled by the (1) BN_dec2bn or (2) BN_hex2bn function, related to crypto/bn/bn.h and crypto/bn/bn_print.c. ..read more

Memory leak in the SRP_VBASE_get_by_user implementation in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g allows remote attackers to cause a denial of service (memory consumption) by providing an invalid username in a connection attempt, related to apps/s_server.c and crypto/srp/srp_vfy.c. ..read more

The fmtstr function in crypto/bio/b_print.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g improperly calculates string lengths, which allows remote attackers to cause a denial of service (overflow and out-of-bounds read) or possibly have unspecified other impact via a long string, as demonstrated by a large amount of ASN.1 data, a different vulnerability than CVE-2016-2842. ..read more

The SSLv2 protocol, as used in OpenSSL before 1.0.1s and 1.0.2 before 1.0.2g and other products, requires a server to send a ServerVerify message before establishing that a client possesses certain plaintext RSA data, which makes it easier for remote attackers to decrypt TLS ciphertext data by leveraging a Bleichenbacher RSA padding oracle, aka a "DROWN" attack. ..read more

Integer overflow in the EVP_EncodeUpdate function in crypto/evp/encode.c in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to cause a denial of service (heap memory corruption) via a large amount of binary data. ..read more

Integer overflow in the EVP_EncryptUpdate function in crypto/evp/evp_enc.c in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to cause a denial of service (heap memory corruption) via a large amount of data. ..read more

The AES-NI implementation in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h does not consider memory allocation during a certain padding check, which allows remote attackers to obtain sensitive cleartext information via a padding-oracle attack against an AES CBC session. NOTE: this vulnerability exists because of an incorrect fix for CVE-2013-0169. ..read more

The asn1_d2i_read_bio function in crypto/asn1/a_d2i_fp.c in the ASN.1 BIO implementation in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to cause a denial of service (memory consumption) via a short invalid encoding. ..read more

The X509_NAME_oneline function in crypto/x509/x509_obj.c in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to obtain sensitive information from process stack memory or cause a denial of service (buffer over-read) via crafted EBCDIC ASN.1 data. ..read more

OpenSSL through 1.0.2h incorrectly uses pointer arithmetic for heap-buffer boundary checks, which might allow remote attackers to cause a denial of service (integer overflow and application crash) or possibly have unspecified other impact by leveraging unexpected malloc behavior, related to s3_srvr.c, ssl_sess.c, and t1_lib.c. ..read more

The dsa_sign_setup function in crypto/dsa/dsa_ossl.c in OpenSSL through 1.0.2h does not properly ensure the use of constant-time operations, which makes it easier for local users to discover a DSA private key via a timing side-channel attack. ..read more

The DTLS implementation in OpenSSL before 1.1.0 does not properly restrict the lifetime of queue entries associated with unused out-of-order messages, which allows remote attackers to cause a denial of service (memory consumption) by maintaining many crafted DTLS sessions simultaneously, related to d1_lib.c, statem_dtls.c, statem_lib.c, and statem_srvr.c. ..read more

The TS_OBJ_print_bio function in crypto/ts/ts_lib.c in the X.509 Public Key Infrastructure Time-Stamp Protocol (TSP) implementation in OpenSSL through 1.0.2h allows remote attackers to cause a denial of service (out-of-bounds read and application crash) via a crafted time-stamp file that is mishandled by the "openssl ts" command. ..read more

The Anti-Replay feature in the DTLS implementation in OpenSSL before 1.1.0 mishandles early use of a new epoch number in conjunction with a large sequence number, which allows remote attackers to cause a denial of service (false-positive packet drops) via spoofed DTLS records, related to rec_layer_d1.c and ssl3_record.c. ..read more

The BN_bn2dec function in crypto/bn/bn_print.c in OpenSSL before 1.1.0 does not properly validate division results, which allows remote attackers to cause a denial of service (out-of-bounds write and application crash) or possibly have unspecified other impact via unknown vectors. ..read more

The DES and Triple DES ciphers, as used in the TLS, SSH, and IPSec protocols and other protocols and products, have a birthday bound of approximately four billion blocks, which makes it easier for remote attackers to obtain cleartext data via a birthday attack against a long-duration encrypted session, as demonstrated by an HTTPS session using Triple DES in CBC mode, aka a "Sweet32" attack. ..read more

The doapr_outch function in crypto/bio/b_print.c in OpenSSL 1.0.1 before 1.0.1s and 1.0.2 before 1.0.2g does not verify that a certain memory allocation succeeds, which allows remote attackers to cause a denial of service (out-of-bounds write or memory consumption) or possibly have unspecified other impact via a long string, as demonstrated by a large amount of ASN.1 data, a different vulnerability than CVE-2016-0799. ..read more

The tls_decrypt_ticket function in ssl/t1_lib.c in OpenSSL before 1.1.0 does not consider the HMAC size during validation of the ticket length, which allows remote attackers to cause a denial of service via a ticket that is too short. ..read more

Integer overflow in the MDC2_Update function in crypto/mdc2/mdc2dgst.c in OpenSSL before 1.1.0 allows remote attackers to cause a denial of service (out-of-bounds write and application crash) or possibly have unspecified other impact via unknown vectors. ..read more

Multiple memory leaks in t1_lib.c in OpenSSL before 1.0.1u, 1.0.2 before 1.0.2i, and 1.1.0 before 1.1.0a allow remote attackers to cause a denial of service (memory consumption) via large OCSP Status Request extensions. ..read more

The certificate parser in OpenSSL before 1.0.1u and 1.0.2 before 1.0.2i might allow remote attackers to cause a denial of service (out-of-bounds read) via crafted certificate operations, related to s3_clnt.c and s3_srvr.c. ..read more

There is a carry propagating bug in the Broadwell-specific Montgomery multiplication procedure in OpenSSL 1.0.2 and 1.1.0 before 1.1.0c that handles input lengths divisible by, but longer than 256 bits. Analysis suggests that attacks against RSA, DSA and DH private keys are impossible. This is because the subroutine in question is not used in operations with the private key itself and an input of the attacker's direct choice. Otherwise the bug can manifest itself as transient authentication and key negotiation failures or reproducible erroneous outcome of public-key operations with specially crafted input. Among EC algorithms only Brainpool P-512 curves are affected and one presumably can attack ECDH key negotiation. Impact was not analyzed in detail, because pre-requisites for attack are considered unlikely. Namely multiple clients have to choose the curve in question and the server has to share the private key among them, neither of which is default behaviour. Even then only clients that chose the curve will be affected. ..read more

A denial of service flaw was found in OpenSSL 0.9.8, 1.0.1, 1.0.2 through 1.0.2h, and 1.1.0 in the way the TLS/SSL protocol defined processing of ALERT packets during a connection handshake. A remote attacker could use this flaw to make a TLS/SSL server consume an excessive amount of CPU and fail to accept connections from other clients. ..read more

If an SSL/TLS server or client is running on a 32-bit host, and a specific cipher is being used, then a truncated packet can cause that server or client to perform an out-of-bounds read, usually resulting in a crash. For OpenSSL 1.1.0, the crash can be triggered when using CHACHA20/POLY1305; users should upgrade to 1.1.0d. For Openssl 1.0.2, the crash can be triggered when using RC4-MD5; users who have not disabled that algorithm should update to 1.0.2k. ..read more

There is a carry propagating bug in the x86_64 Montgomery squaring procedure in OpenSSL 1.0.2 before 1.0.2k and 1.1.0 before 1.1.0d. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. For example this can occur by default in OpenSSL DHE based SSL/TLS ciphersuites. Note: This issue is very similar to CVE-2015-3193 but must be treated as a separate problem. ..read more

While parsing an IPAddressFamily extension in an X.509 certificate, it is possible to do a one-byte overread. This would result in an incorrect text display of the certificate. This bug has been present since 2006 and is present in all versions of OpenSSL before 1.0.2m and 1.1.0g. ..read more

There is a carry propagating bug in the x86_64 Montgomery squaring procedure in OpenSSL before 1.0.2m and 1.1.0 before 1.1.0g. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. This only affects processors that support the BMI1, BMI2 and ADX extensions like Intel Broadwell (5th generation) and later or AMD Ryzen. ..read more

OpenSSL 1.0.2 (starting from version 1.0.2b) introduced an "error state" mechanism. The intent was that if a fatal error occurred during a handshake then OpenSSL would move into the error state and would immediately fail if you attempted to continue the handshake. This works as designed for the explicit handshake functions (SSL_do_handshake(), SSL_accept() and SSL_connect()), however due to a bug it does not work correctly if SSL_read() or SSL_write() is called directly. In that scenario, if the handshake fails then a fatal error will be returned in the initial function call. If SSL_read()/SSL_write() is subsequently called by the application for the same SSL object then it will succeed and the data is passed without being decrypted/encrypted directly from the SSL/TLS record layer. In order to exploit this issue an application bug would have to be present that resulted in a call to SSL_read()/SSL_write() being issued after having already received a fatal error. OpenSSL version 1.0.2b-1.0.2m are affected. Fixed in OpenSSL 1.0.2n. OpenSSL 1.1.0 is not affected. ..read more

There is an overflow bug in the AVX2 Montgomery multiplication procedure used in exponentiation with 1024-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH1024 are considered just feasible, because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be significant. However, for an attack on TLS to be meaningful, the server would have to share the DH1024 private key among multiple clients, which is no longer an option since CVE-2016-0701. This only affects processors that support the AVX2 but not ADX extensions like Intel Haswell (4th generation). Note: The impact from this issue is similar to CVE-2017-3736, CVE-2017-3732 and CVE-2015-3193. OpenSSL version 1.0.2-1.0.2m and 1.1.0-1.1.0g are affected. Fixed in OpenSSL 1.0.2n. Due to the low severity of this issue we are not issuing a new release of OpenSSL 1.1.0 at this time. The fix will be included in OpenSSL 1.1.0h when it becomes available. The fix is also available in commit e502cc86d in the OpenSSL git repository. ..read more

The OpenSSL RSA Key generation algorithm has been shown to be vulnerable to a cache timing side channel attack. An attacker with sufficient access to mount cache timing attacks during the RSA key generation process could recover the private key. Fixed in OpenSSL 1.1.0i-dev (Affected 1.1.0-1.1.0h). Fixed in OpenSSL 1.0.2p-dev (Affected 1.0.2b-1.0.2o). ..read more

Constructed ASN.1 types with a recursive definition (such as can be found in PKCS7) could eventually exceed the stack given malicious input with excessive recursion. This could result in a Denial Of Service attack. There are no such structures used within SSL/TLS that come from untrusted sources so this is considered safe. Fixed in OpenSSL 1.1.0h (Affected 1.1.0-1.1.0g). Fixed in OpenSSL 1.0.2o (Affected 1.0.2b-1.0.2n). ..read more

Simultaneous Multi-threading (SMT) in processors can enable local users to exploit software vulnerable to timing attacks via a side-channel timing attack on 'port contention'. ..read more

Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s). ..read more

There is an overflow bug in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME. Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d). Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t). ..read more

OpenSSL has internal defaults for a directory tree where it can find a configuration file as well as certificates used for verification in TLS. This directory is most commonly referred to as OPENSSLDIR, and is configurable with the --prefix / --openssldir configuration options. For OpenSSL versions 1.1.0 and 1.1.1, the mingw configuration targets assume that resulting programs and libraries are installed in a Unix-like environment and the default prefix for program installation as well as for OPENSSLDIR should be '/usr/local'. However, mingw programs are Windows programs, and as such, find themselves looking at sub-directories of 'C:/usr/local', which may be world writable, which enables untrusted users to modify OpenSSL's default configuration, insert CA certificates, modify (or even replace) existing engine modules, etc. For OpenSSL 1.0.2, '/usr/local/ssl' is used as default for OPENSSLDIR on all Unix and Windows targets, including Visual C builds. However, some build instructions for the diverse Windows targets on 1.0.2 encourage you to specify your own --prefix. OpenSSL versions 1.1.1, 1.1.0 and 1.0.2 are affected by this issue. Due to the limited scope of affected deployments this has been assessed as low severity and therefore we are not creating new releases at this time. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s). ..read more

If an application encounters a fatal protocol error and then calls SSL_shutdown() twice (once to send a close_notify, and once to receive one) then OpenSSL can respond differently to the calling application if a 0 byte record is received with invalid padding compared to if a 0 byte record is received with an invalid MAC. If the application then behaves differently based on that in a way that is detectable to the remote peer, then this amounts to a padding oracle that could be used to decrypt data. In order for this to be exploitable "non-stitched" ciphersuites must be in use. Stitched ciphersuites are optimised implementations of certain commonly used ciphersuites. Also the application must call SSL_shutdown() twice even if a protocol error has occurred (applications should not do this but some do anyway). Fixed in OpenSSL 1.0.2r (Affected 1.0.2-1.0.2q). ..read more

In situations where an attacker receives automated notification of the success or failure of a decryption attempt an attacker, after sending a very large number of messages to be decrypted, can recover a CMS/PKCS7 transported encryption key or decrypt any RSA encrypted message that was encrypted with the public RSA key, using a Bleichenbacher padding oracle attack. Applications are not affected if they use a certificate together with the private RSA key to the CMS_decrypt or PKCS7_decrypt functions to select the correct recipient info to decrypt. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s). ..read more

The Raccoon attack exploits a flaw in the TLS specification which can lead to an attacker being able to compute the pre-master secret in connections which have used a Diffie-Hellman (DH) based ciphersuite. In such a case this would result in the attacker being able to eavesdrop on all encrypted communications sent over that TLS connection. The attack can only be exploited if an implementation re-uses a DH secret across multiple TLS connections. Note that this issue only impacts DH ciphersuites and not ECDH ciphersuites. This issue affects OpenSSL 1.0.2 which is out of support and no longer receiving public updates. OpenSSL 1.1.1 is not vulnerable to this issue. Fixed in OpenSSL 1.0.2w (Affected 1.0.2-1.0.2v). ..read more

Calls to EVP_CipherUpdate, EVP_EncryptUpdate and EVP_DecryptUpdate may overflow the output length argument in some cases where the input length is close to the maximum permissable length for an integer on the platform. In such cases the return value from the function call will be 1 (indicating success), but the output length value will be negative. This could cause applications to behave incorrectly or crash. OpenSSL versions 1.1.1i and below are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1j. OpenSSL versions 1.0.2x and below are affected by this issue. However OpenSSL 1.0.2 is out of support and no longer receiving public updates. Premium support customers of OpenSSL 1.0.2 should upgrade to 1.0.2y. Other users should upgrade to 1.1.1j. Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i). Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x). ..read more

The OpenSSL public API function X509_issuer_and_serial_hash() attempts to create a unique hash value based on the issuer and serial number data contained within an X509 certificate. However it fails to correctly handle any errors that may occur while parsing the issuer field (which might occur if the issuer field is maliciously constructed). This may subsequently result in a NULL pointer deref and a crash leading to a potential denial of service attack. The function X509_issuer_and_serial_hash() is never directly called by OpenSSL itself so applications are only vulnerable if they use this function directly and they use it on certificates that may have been obtained from untrusted sources. OpenSSL versions 1.1.1i and below are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1j. OpenSSL versions 1.0.2x and below are affected by this issue. However OpenSSL 1.0.2 is out of support and no longer receiving public updates. Premium support customers of OpenSSL 1.0.2 should upgrade to 1.0.2y. Other users should upgrade to 1.1.1j. Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i). Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x). ..read more

ASN.1 strings are represented internally within OpenSSL as an ASN1_STRING structure which contains a buffer holding the string data and a field holding the buffer length. This contrasts with normal C strings which are repesented as a buffer for the string data which is terminated with a NUL (0) byte. Although not a strict requirement, ASN.1 strings that are parsed using OpenSSL's own "d2i" functions (and other similar parsing functions) as well as any string whose value has been set with the ASN1_STRING_set() function will additionally NUL terminate the byte array in the ASN1_STRING structure. However, it is possible for applications to directly construct valid ASN1_STRING structures which do not NUL terminate the byte array by directly setting the "data" and "length" fields in the ASN1_STRING array. This can also happen by using the ASN1_STRING_set0() function. Numerous OpenSSL functions that print ASN.1 data have been found to assume that the ASN1_STRING byte array will be NUL terminated, even though this is not guaranteed for strings that have been directly constructed. Where an application requests an ASN.1 structure to be printed, and where that ASN.1 structure contains ASN1_STRINGs that have been directly constructed by the application without NUL terminating the "data" field, then a read buffer overrun can occur. The same thing can also occur during name constraints processing of certificates (for example if a certificate has been directly constructed by the application instead of loading it via the OpenSSL parsing functions, and the certificate contains non NUL terminated ASN1_STRING structures). It can also occur in the X509_get1_email(), X509_REQ_get1_email() and X509_get1_ocsp() functions. If a malicious actor can cause an application to directly construct an ASN1_STRING and then process it through one of the affected OpenSSL functions then this issue could be hit. This might result in a crash (causing a Denial of Service attack). It could also result in the disclosure of private memory contents (such as private keys, or sensitive plaintext). Fixed in OpenSSL 1.1.1l (Affected 1.1.1-1.1.1k). Fixed in OpenSSL 1.0.2za (Affected 1.0.2-1.0.2y). ..read more

There is a carry propagation bug in the MIPS32 and MIPS64 squaring procedure. Many EC algorithms are affected, including some of the TLS 1.3 default curves. Impact was not analyzed in detail, because the pre-requisites for attack are considered unlikely and include reusing private keys. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be significant. However, for an attack on TLS to be meaningful, the server would have to share the DH private key among multiple clients, which is no longer an option since CVE-2016-0701. This issue affects OpenSSL versions 1.0.2, 1.1.1 and 3.0.0. It was addressed in the releases of 1.1.1m and 3.0.1 on the 15th of December 2021. For the 1.0.2 release it is addressed in git commit 6fc1aaaf3 that is available to premium support customers only. It will be made available in 1.0.2zc when it is released. The issue only affects OpenSSL on MIPS platforms. Fixed in OpenSSL 3.0.1 (Affected 3.0.0). Fixed in OpenSSL 1.1.1m (Affected 1.1.1-1.1.1l). Fixed in OpenSSL 1.0.2zc-dev (Affected 1.0.2-1.0.2zb). ..read more

The BN_mod_sqrt() function, which computes a modular square root, contains a bug that can cause it to loop forever for non-prime moduli. Internally this function is used when parsing certificates that contain elliptic curve public keys in compressed form or explicit elliptic curve parameters with a base point encoded in compressed form. It is possible to trigger the infinite loop by crafting a certificate that has invalid explicit curve parameters. Since certificate parsing happens prior to verification of the certificate signature, any process that parses an externally supplied certificate may thus be subject to a denial of service attack. The infinite loop can also be reached when parsing crafted private keys as they can contain explicit elliptic curve parameters. Thus vulnerable situations include: - TLS clients consuming server certificates - TLS servers consuming client certificates - Hosting providers taking certificates or private keys from customers - Certificate authorities parsing certification requests from subscribers - Anything else which parses ASN.1 elliptic curve parameters Also any other applications that use the BN_mod_sqrt() where the attacker can control the parameter values are vulnerable to this DoS issue. In the OpenSSL 1.0.2 version the public key is not parsed during initial parsing of the certificate which makes it slightly harder to trigger the infinite loop. However any operation which requires the public key from the certificate will trigger the infinite loop. In particular the attacker can use a self-signed certificate to trigger the loop during verification of the certificate signature. This issue affects OpenSSL versions 1.0.2, 1.1.1 and 3.0. It was addressed in the releases of 1.1.1n and 3.0.2 on the 15th March 2022. Fixed in OpenSSL 3.0.2 (Affected 3.0.0,3.0.1). Fixed in OpenSSL 1.1.1n (Affected 1.1.1-1.1.1m). Fixed in OpenSSL 1.0.2zd (Affected 1.0.2-1.0.2zc). ..read more

The c_rehash script does not properly sanitise shell metacharacters to prevent command injection. This script is distributed by some operating systems in a manner where it is automatically executed. On such operating systems, an attacker could execute arbitrary commands with the privileges of the script. Use of the c_rehash script is considered obsolete and should be replaced by the OpenSSL rehash command line tool. Fixed in OpenSSL 3.0.3 (Affected 3.0.0,3.0.1,3.0.2). Fixed in OpenSSL 1.1.1o (Affected 1.1.1-1.1.1n). Fixed in OpenSSL 1.0.2ze (Affected 1.0.2-1.0.2zd). ..read more

In addition to the c_rehash shell command injection identified in CVE-2022-1292, further circumstances where the c_rehash script does not properly sanitise shell metacharacters to prevent command injection were found by code review. When the CVE-2022-1292 was fixed it was not discovered that there are other places in the script where the file names of certificates being hashed were possibly passed to a command executed through the shell. This script is distributed by some operating systems in a manner where it is automatically executed. On such operating systems, an attacker could execute arbitrary commands with the privileges of the script. Use of the c_rehash script is considered obsolete and should be replaced by the OpenSSL rehash command line tool. Fixed in OpenSSL 3.0.4 (Affected 3.0.0,3.0.1,3.0.2,3.0.3). Fixed in OpenSSL 1.1.1p (Affected 1.1.1-1.1.1o). Fixed in OpenSSL 1.0.2zf (Affected 1.0.2-1.0.2ze). ..read more

A timing based side channel exists in the OpenSSL RSA Decryption implementation which could be sufficient to recover a plaintext across a network in a Bleichenbacher style attack. To achieve a successful decryption an attacker would have to be able to send a very large number of trial messages for decryption. The vulnerability affects all RSA padding modes: PKCS#1 v1.5, RSA-OEAP and RSASVE. For example, in a TLS connection, RSA is commonly used by a client to send an encrypted pre-master secret to the server. An attacker that had observed a genuine connection between a client and a server could use this flaw to send trial messages to the server and record the time taken to process them. After a sufficiently large number of messages the attacker could recover the pre-master secret used for the original connection and thus be able to decrypt the application data sent over that connection. ..read more

The public API function BIO_new_NDEF is a helper function used for streaming ASN.1 data via a BIO. It is primarily used internally to OpenSSL to support the SMIME, CMS and PKCS7 streaming capabilities, but may also be called directly by end user applications. The function receives a BIO from the caller, prepends a new BIO_f_asn1 filter BIO onto the front of it to form a BIO chain, and then returns the new head of the BIO chain to the caller. Under certain conditions, for example if a CMS recipient public key is invalid, the new filter BIO is freed and the function returns a NULL result indicating a failure. However, in this case, the BIO chain is not properly cleaned up and the BIO passed by the caller still retains internal pointers to the previously freed filter BIO. If the caller then goes on to call BIO_pop() on the BIO then a use-after-free will occur. This will most likely result in a crash. This scenario occurs directly in the internal function B64_write_ASN1() which may cause BIO_new_NDEF() to be called and will subsequently call BIO_pop() on the BIO. This internal function is in turn called by the public API functions PEM_write_bio_ASN1_stream, PEM_write_bio_CMS_stream, PEM_write_bio_PKCS7_stream, SMIME_write_ASN1, SMIME_write_CMS and SMIME_write_PKCS7. Other public API functions that may be impacted by this include i2d_ASN1_bio_stream, BIO_new_CMS, BIO_new_PKCS7, i2d_CMS_bio_stream and i2d_PKCS7_bio_stream. The OpenSSL cms and smime command line applications are similarly affected. ..read more

There is a type confusion vulnerability relating to X.400 address processing inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING but the public structure definition for GENERAL_NAME incorrectly specified the type of the x400Address field as ASN1_TYPE. This field is subsequently interpreted by the OpenSSL function GENERAL_NAME_cmp as an ASN1_TYPE rather than an ASN1_STRING. When CRL checking is enabled (i.e. the application sets the X509_V_FLAG_CRL_CHECK flag), this vulnerability may allow an attacker to pass arbitrary pointers to a memcmp call, enabling them to read memory contents or enact a denial of service. In most cases, the attack requires the attacker to provide both the certificate chain and CRL, neither of which need to have a valid signature. If the attacker only controls one of these inputs, the other input must already contain an X.400 address as a CRL distribution point, which is uncommon. As such, this vulnerability is most likely to only affect applications which have implemented their own functionality for retrieving CRLs over a network. ..read more